/* * copyright (c) 2001 Fabrice Bellard * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef AVFORMAT_AVFORMAT_H #define AVFORMAT_AVFORMAT_H /** * @file * @ingroup libavf * Main libavformat public API header */ /** * @defgroup libavf libavformat * I/O and Muxing/Demuxing Library * * Libavformat (lavf) is a library for dealing with various media container * formats. Its main two purposes are demuxing - i.e. splitting a media file * into component streams, and the reverse process of muxing - writing supplied * data in a specified container format. It also has an @ref lavf_io * "I/O module" which supports a number of protocols for accessing the data (e.g. * file, tcp, http and others). * Unless you are absolutely sure you won't use libavformat's network * capabilities, you should also call avformat_network_init(). * * A supported input format is described by an AVInputFormat struct, conversely * an output format is described by AVOutputFormat. You can iterate over all * input/output formats using the av_demuxer_iterate / av_muxer_iterate() functions. * The protocols layer is not part of the public API, so you can only get the names * of supported protocols with the avio_enum_protocols() function. * * Main lavf structure used for both muxing and demuxing is AVFormatContext, * which exports all information about the file being read or written. As with * most Libavformat structures, its size is not part of public ABI, so it cannot be * allocated on stack or directly with av_malloc(). To create an * AVFormatContext, use avformat_alloc_context() (some functions, like * avformat_open_input() might do that for you). * * Most importantly an AVFormatContext contains: * @li the @ref AVFormatContext.iformat "input" or @ref AVFormatContext.oformat * "output" format. It is either autodetected or set by user for input; * always set by user for output. * @li an @ref AVFormatContext.streams "array" of AVStreams, which describe all * elementary streams stored in the file. AVStreams are typically referred to * using their index in this array. * @li an @ref AVFormatContext.pb "I/O context". It is either opened by lavf or * set by user for input, always set by user for output (unless you are dealing * with an AVFMT_NOFILE format). * * @section lavf_options Passing options to (de)muxers * It is possible to configure lavf muxers and demuxers using the @ref avoptions * mechanism. Generic (format-independent) libavformat options are provided by * AVFormatContext, they can be examined from a user program by calling * av_opt_next() / av_opt_find() on an allocated AVFormatContext (or its AVClass * from avformat_get_class()). Private (format-specific) options are provided by * AVFormatContext.priv_data if and only if AVInputFormat.priv_class / * AVOutputFormat.priv_class of the corresponding format struct is non-NULL. * Further options may be provided by the @ref AVFormatContext.pb "I/O context", * if its AVClass is non-NULL, and the protocols layer. See the discussion on * nesting in @ref avoptions documentation to learn how to access those. * * @section urls * URL strings in libavformat are made of a scheme/protocol, a ':', and a * scheme specific string. URLs without a scheme and ':' used for local files * are supported but deprecated. "file:" should be used for local files. * * It is important that the scheme string is not taken from untrusted * sources without checks. * * Note that some schemes/protocols are quite powerful, allowing access to * both local and remote files, parts of them, concatenations of them, local * audio and video devices and so on. * * @{ * * @defgroup lavf_decoding Demuxing * @{ * Demuxers read a media file and split it into chunks of data (@em packets). A * @ref AVPacket "packet" contains one or more encoded frames which belongs to a * single elementary stream. In the lavf API this process is represented by the * avformat_open_input() function for opening a file, av_read_frame() for * reading a single packet and finally avformat_close_input(), which does the * cleanup. * * @section lavf_decoding_open Opening a media file * The minimum information required to open a file is its URL, which * is passed to avformat_open_input(), as in the following code: * @code * const char *url = "file:in.mp3"; * AVFormatContext *s = NULL; * int ret = avformat_open_input(&s, url, NULL, NULL); * if (ret < 0) * abort(); * @endcode * The above code attempts to allocate an AVFormatContext, open the * specified file (autodetecting the format) and read the header, exporting the * information stored there into s. Some formats do not have a header or do not * store enough information there, so it is recommended that you call the * avformat_find_stream_info() function which tries to read and decode a few * frames to find missing information. * * In some cases you might want to preallocate an AVFormatContext yourself with * avformat_alloc_context() and do some tweaking on it before passing it to * avformat_open_input(). One such case is when you want to use custom functions * for reading input data instead of lavf internal I/O layer. * To do that, create your own AVIOContext with avio_alloc_context(), passing * your reading callbacks to it. Then set the @em pb field of your * AVFormatContext to newly created AVIOContext. * * Since the format of the opened file is in general not known until after * avformat_open_input() has returned, it is not possible to set demuxer private * options on a preallocated context. Instead, the options should be passed to * avformat_open_input() wrapped in an AVDictionary: * @code * AVDictionary *options = NULL; * av_dict_set(&options, "video_size", "640x480", 0); * av_dict_set(&options, "pixel_format", "rgb24", 0); * * if (avformat_open_input(&s, url, NULL, &options) < 0) * abort(); * av_dict_free(&options); * @endcode * This code passes the private options 'video_size' and 'pixel_format' to the * demuxer. They would be necessary for e.g. the rawvideo demuxer, since it * cannot know how to interpret raw video data otherwise. If the format turns * out to be something different than raw video, those options will not be * recognized by the demuxer and therefore will not be applied. Such unrecognized * options are then returned in the options dictionary (recognized options are * consumed). The calling program can handle such unrecognized options as it * wishes, e.g. * @code * AVDictionaryEntry *e; * if (e = av_dict_get(options, "", NULL, AV_DICT_IGNORE_SUFFIX)) { * fprintf(stderr, "Option %s not recognized by the demuxer.\n", e->key); * abort(); * } * @endcode * * After you have finished reading the file, you must close it with * avformat_close_input(). It will free everything associated with the file. * * @section lavf_decoding_read Reading from an opened file * Reading data from an opened AVFormatContext is done by repeatedly calling * av_read_frame() on it. Each call, if successful, will return an AVPacket * containing encoded data for one AVStream, identified by * AVPacket.stream_index. This packet may be passed straight into the libavcodec * decoding functions avcodec_send_packet() or avcodec_decode_subtitle2() if the * caller wishes to decode the data. * * AVPacket.pts, AVPacket.dts and AVPacket.duration timing information will be * set if known. They may also be unset (i.e. AV_NOPTS_VALUE for * pts/dts, 0 for duration) if the stream does not provide them. The timing * information will be in AVStream.time_base units, i.e. it has to be * multiplied by the timebase to convert them to seconds. * * A packet returned by av_read_frame() is always reference-counted, * i.e. AVPacket.buf is set and the user may keep it indefinitely. * The packet must be freed with av_packet_unref() when it is no * longer needed. * * @section lavf_decoding_seek Seeking * @} * * @defgroup lavf_encoding Muxing * @{ * Muxers take encoded data in the form of @ref AVPacket "AVPackets" and write * it into files or other output bytestreams in the specified container format. * * The main API functions for muxing are avformat_write_header() for writing the * file header, av_write_frame() / av_interleaved_write_frame() for writing the * packets and av_write_trailer() for finalizing the file. * * At the beginning of the muxing process, the caller must first call * avformat_alloc_context() to create a muxing context. The caller then sets up * the muxer by filling the various fields in this context: * * - The @ref AVFormatContext.oformat "oformat" field must be set to select the * muxer that will be used. * - Unless the format is of the AVFMT_NOFILE type, the @ref AVFormatContext.pb * "pb" field must be set to an opened IO context, either returned from * avio_open2() or a custom one. * - Unless the format is of the AVFMT_NOSTREAMS type, at least one stream must * be created with the avformat_new_stream() function. The caller should fill * the @ref AVStream.codecpar "stream codec parameters" information, such as the * codec @ref AVCodecParameters.codec_type "type", @ref AVCodecParameters.codec_id * "id" and other parameters (e.g. width / height, the pixel or sample format, * etc.) as known. The @ref AVStream.time_base "stream timebase" should * be set to the timebase that the caller desires to use for this stream (note * that the timebase actually used by the muxer can be different, as will be * described later). * - It is advised to manually initialize only the relevant fields in * AVCodecParameters, rather than using @ref avcodec_parameters_copy() during * remuxing: there is no guarantee that the codec context values remain valid * for both input and output format contexts. * - The caller may fill in additional information, such as @ref * AVFormatContext.metadata "global" or @ref AVStream.metadata "per-stream" * metadata, @ref AVFormatContext.chapters "chapters", @ref * AVFormatContext.programs "programs", etc. as described in the * AVFormatContext documentation. Whether such information will actually be * stored in the output depends on what the container format and the muxer * support. * * When the muxing context is fully set up, the caller must call * avformat_write_header() to initialize the muxer internals and write the file * header. Whether anything actually is written to the IO context at this step * depends on the muxer, but this function must always be called. Any muxer * private options must be passed in the options parameter to this function. * * The data is then sent to the muxer by repeatedly calling av_write_frame() or * av_interleaved_write_frame() (consult those functions' documentation for * discussion on the difference between them; only one of them may be used with * a single muxing context, they should not be mixed). Do note that the timing * information on the packets sent to the muxer must be in the corresponding * AVStream's timebase. That timebase is set by the muxer (in the * avformat_write_header() step) and may be different from the timebase * requested by the caller. * * Once all the data has been written, the caller must call av_write_trailer() * to flush any buffered packets and finalize the output file, then close the IO * context (if any) and finally free the muxing context with * avformat_free_context(). * @} * * @defgroup lavf_io I/O Read/Write * @{ * @section lavf_io_dirlist Directory listing * The directory listing API makes it possible to list files on remote servers. * * Some of possible use cases: * - an "open file" dialog to choose files from a remote location, * - a recursive media finder providing a player with an ability to play all * files from a given directory. * * @subsection lavf_io_dirlist_open Opening a directory * At first, a directory needs to be opened by calling avio_open_dir() * supplied with a URL and, optionally, ::AVDictionary containing * protocol-specific parameters. The function returns zero or positive * integer and allocates AVIODirContext on success. * * @code * AVIODirContext *ctx = NULL; * if (avio_open_dir(&ctx, "smb://example.com/some_dir", NULL) < 0) { * fprintf(stderr, "Cannot open directory.\n"); * abort(); * } * @endcode * * This code tries to open a sample directory using smb protocol without * any additional parameters. * * @subsection lavf_io_dirlist_read Reading entries * Each directory's entry (i.e. file, another directory, anything else * within ::AVIODirEntryType) is represented by AVIODirEntry. * Reading consecutive entries from an opened AVIODirContext is done by * repeatedly calling avio_read_dir() on it. Each call returns zero or * positive integer if successful. Reading can be stopped right after the * NULL entry has been read -- it means there are no entries left to be * read. The following code reads all entries from a directory associated * with ctx and prints their names to standard output. * @code * AVIODirEntry *entry = NULL; * for (;;) { * if (avio_read_dir(ctx, &entry) < 0) { * fprintf(stderr, "Cannot list directory.\n"); * abort(); * } * if (!entry) * break; * printf("%s\n", entry->name); * avio_free_directory_entry(&entry); * } * @endcode * @} * * @defgroup lavf_codec Demuxers * @{ * @defgroup lavf_codec_native Native Demuxers * @{ * @} * @defgroup lavf_codec_wrappers External library wrappers * @{ * @} * @} * @defgroup lavf_protos I/O Protocols * @{ * @} * @defgroup lavf_internal Internal * @{ * @} * @} */ #include <stdio.h> /* FILE */ #include "libavcodec/codec_par.h" #include "libavcodec/defs.h" #include "libavcodec/packet.h" #include "libavutil/dict.h" #include "libavutil/log.h" #include "avio.h" #include "libavformat/version_major.h" #ifndef HAVE_AV_CONFIG_H /* When included as part of the ffmpeg build, only include the major version * to avoid unnecessary rebuilds. When included externally, keep including * the full version information. */ #include "libavformat/version.h" #include "libavutil/frame.h" #include "libavcodec/codec.h" #endif struct AVFormatContext; struct AVFrame; /** * @defgroup metadata_api Public Metadata API * @{ * @ingroup libavf * The metadata API allows libavformat to export metadata tags to a client * application when demuxing. Conversely it allows a client application to * set metadata when muxing. * * Metadata is exported or set as pairs of key/value strings in the 'metadata' * fields of the AVFormatContext, AVStream, AVChapter and AVProgram structs * using the @ref lavu_dict "AVDictionary" API. Like all strings in FFmpeg, * metadata is assumed to be UTF-8 encoded Unicode. Note that metadata * exported by demuxers isn't checked to be valid UTF-8 in most cases. * * Important concepts to keep in mind: * - Keys are unique; there can never be 2 tags with the same key. This is * also meant semantically, i.e., a demuxer should not knowingly produce * several keys that are literally different but semantically identical. * E.g., key=Author5, key=Author6. In this example, all authors must be * placed in the same tag. * - Metadata is flat, not hierarchical; there are no subtags. If you * want to store, e.g., the email address of the child of producer Alice * and actor Bob, that could have key=alice_and_bobs_childs_email_address. * - Several modifiers can be applied to the tag name. This is done by * appending a dash character ('-') and the modifier name in the order * they appear in the list below -- e.g. foo-eng-sort, not foo-sort-eng. * - language -- a tag whose value is localized for a particular language * is appended with the ISO 639-2/B 3-letter language code. * For example: Author-ger=Michael, Author-eng=Mike * The original/default language is in the unqualified "Author" tag. * A demuxer should set a default if it sets any translated tag. * - sorting -- a modified version of a tag that should be used for * sorting will have '-sort' appended. E.g. artist="The Beatles", * artist-sort="Beatles, The". * - Some protocols and demuxers support metadata updates. After a successful * call to av_read_frame(), AVFormatContext.event_flags or AVStream.event_flags * will be updated to indicate if metadata changed. In order to detect metadata * changes on a stream, you need to loop through all streams in the AVFormatContext * and check their individual event_flags. * * - Demuxers attempt to export metadata in a generic format, however tags * with no generic equivalents are left as they are stored in the container. * Follows a list of generic tag names: * @verbatim album -- name of the set this work belongs to album_artist -- main creator of the set/album, if different from artist. e.g. "Various Artists" for compilation albums. artist -- main creator of the work comment -- any additional description of the file. composer -- who composed the work, if different from artist. copyright -- name of copyright holder. creation_time-- date when the file was created, preferably in ISO 8601. date -- date when the work was created, preferably in ISO 8601. disc -- number of a subset, e.g. disc in a multi-disc collection. encoder -- name/settings of the software/hardware that produced the file. encoded_by -- person/group who created the file. filename -- original name of the file. genre -- <self-evident>. language -- main language in which the work is performed, preferably in ISO 639-2 format. Multiple languages can be specified by separating them with commas. performer -- artist who performed the work, if different from artist. E.g for "Also sprach Zarathustra", artist would be "Richard Strauss" and performer "London Philharmonic Orchestra". publisher -- name of the label/publisher. service_name -- name of the service in broadcasting (channel name). service_provider -- name of the service provider in broadcasting. title -- name of the work. track -- number of this work in the set, can be in form current/total. variant_bitrate -- the total bitrate of the bitrate variant that the current stream is part of @endverbatim * * Look in the examples section for an application example how to use the Metadata API. * * @} */ /* packet functions */ /** * Allocate and read the payload of a packet and initialize its * fields with default values. * * @param s associated IO context * @param pkt packet * @param size desired payload size * @return >0 (read size) if OK, AVERROR_xxx otherwise */ int av_get_packet(AVIOContext *s, AVPacket *pkt, int size); /** * Read data and append it to the current content of the AVPacket. * If pkt->size is 0 this is identical to av_get_packet. * Note that this uses av_grow_packet and thus involves a realloc * which is inefficient. Thus this function should only be used * when there is no reasonable way to know (an upper bound of) * the final size. * * @param s associated IO context * @param pkt packet * @param size amount of data to read * @return >0 (read size) if OK, AVERROR_xxx otherwise, previous data * will not be lost even if an error occurs. */ int av_append_packet(AVIOContext *s, AVPacket *pkt, int size); /*************************************************/ /* input/output formats */ struct AVCodecTag; /** * This structure contains the data a format has to probe a file. */ AVProbeData; #define AVPROBE_SCORE_RETRY … #define AVPROBE_SCORE_STREAM_RETRY … #define AVPROBE_SCORE_EXTENSION … #define AVPROBE_SCORE_MIME … #define AVPROBE_SCORE_MAX … #define AVPROBE_PADDING_SIZE … /// Demuxer will use avio_open, no opened file should be provided by the caller. #define AVFMT_NOFILE … #define AVFMT_NEEDNUMBER … /** * The muxer/demuxer is experimental and should be used with caution. * * - demuxers: will not be selected automatically by probing, must be specified * explicitly. */ #define AVFMT_EXPERIMENTAL … #define AVFMT_SHOW_IDS … #define AVFMT_GLOBALHEADER … #define AVFMT_NOTIMESTAMPS … #define AVFMT_GENERIC_INDEX … #define AVFMT_TS_DISCONT … #define AVFMT_VARIABLE_FPS … #define AVFMT_NODIMENSIONS … #define AVFMT_NOSTREAMS … #define AVFMT_NOBINSEARCH … #define AVFMT_NOGENSEARCH … #define AVFMT_NO_BYTE_SEEK … #if FF_API_ALLOW_FLUSH #define AVFMT_ALLOW_FLUSH … #endif #define AVFMT_TS_NONSTRICT … #define AVFMT_TS_NEGATIVE … #define AVFMT_SEEK_TO_PTS … /** * @addtogroup lavf_encoding * @{ */ AVOutputFormat; /** * @} */ /** * @addtogroup lavf_decoding * @{ */ AVInputFormat; /** * @} */ enum AVStreamParseType { … }; AVIndexEntry; /** * The stream should be chosen by default among other streams of the same type, * unless the user has explicitly specified otherwise. */ #define AV_DISPOSITION_DEFAULT … /** * The stream is not in original language. * * @note AV_DISPOSITION_ORIGINAL is the inverse of this disposition. At most * one of them should be set in properly tagged streams. * @note This disposition may apply to any stream type, not just audio. */ #define AV_DISPOSITION_DUB … /** * The stream is in original language. * * @see the notes for AV_DISPOSITION_DUB */ #define AV_DISPOSITION_ORIGINAL … /** * The stream is a commentary track. */ #define AV_DISPOSITION_COMMENT … /** * The stream contains song lyrics. */ #define AV_DISPOSITION_LYRICS … /** * The stream contains karaoke audio. */ #define AV_DISPOSITION_KARAOKE … /** * Track should be used during playback by default. * Useful for subtitle track that should be displayed * even when user did not explicitly ask for subtitles. */ #define AV_DISPOSITION_FORCED … /** * The stream is intended for hearing impaired audiences. */ #define AV_DISPOSITION_HEARING_IMPAIRED … /** * The stream is intended for visually impaired audiences. */ #define AV_DISPOSITION_VISUAL_IMPAIRED … /** * The audio stream contains music and sound effects without voice. */ #define AV_DISPOSITION_CLEAN_EFFECTS … /** * The stream is stored in the file as an attached picture/"cover art" (e.g. * APIC frame in ID3v2). The first (usually only) packet associated with it * will be returned among the first few packets read from the file unless * seeking takes place. It can also be accessed at any time in * AVStream.attached_pic. */ #define AV_DISPOSITION_ATTACHED_PIC … /** * The stream is sparse, and contains thumbnail images, often corresponding * to chapter markers. Only ever used with AV_DISPOSITION_ATTACHED_PIC. */ #define AV_DISPOSITION_TIMED_THUMBNAILS … /** * The stream is intended to be mixed with a spatial audio track. For example, * it could be used for narration or stereo music, and may remain unchanged by * listener head rotation. */ #define AV_DISPOSITION_NON_DIEGETIC … /** * The subtitle stream contains captions, providing a transcription and possibly * a translation of audio. Typically intended for hearing-impaired audiences. */ #define AV_DISPOSITION_CAPTIONS … /** * The subtitle stream contains a textual description of the video content. * Typically intended for visually-impaired audiences or for the cases where the * video cannot be seen. */ #define AV_DISPOSITION_DESCRIPTIONS … /** * The subtitle stream contains time-aligned metadata that is not intended to be * directly presented to the user. */ #define AV_DISPOSITION_METADATA … /** * The stream is intended to be mixed with another stream before presentation. * Used for example to signal the stream contains an image part of a HEIF grid, * or for mix_type=0 in mpegts. */ #define AV_DISPOSITION_DEPENDENT … /** * The video stream contains still images. */ #define AV_DISPOSITION_STILL_IMAGE … /** * @return The AV_DISPOSITION_* flag corresponding to disp or a negative error * code if disp does not correspond to a known stream disposition. */ int av_disposition_from_string(const char *disp); /** * @param disposition a combination of AV_DISPOSITION_* values * @return The string description corresponding to the lowest set bit in * disposition. NULL when the lowest set bit does not correspond * to a known disposition or when disposition is 0. */ const char *av_disposition_to_string(int disposition); /** * Options for behavior on timestamp wrap detection. */ #define AV_PTS_WRAP_IGNORE … #define AV_PTS_WRAP_ADD_OFFSET … #define AV_PTS_WRAP_SUB_OFFSET … /** * Stream structure. * New fields can be added to the end with minor version bumps. * Removal, reordering and changes to existing fields require a major * version bump. * sizeof(AVStream) must not be used outside libav*. */ AVStream; /** * AVStreamGroupTileGrid holds information on how to combine several * independent images on a single canvas for presentation. * * The output should be a @ref AVStreamGroupTileGrid.background "background" * colored @ref AVStreamGroupTileGrid.coded_width "coded_width" x * @ref AVStreamGroupTileGrid.coded_height "coded_height" canvas where a * @ref AVStreamGroupTileGrid.nb_tiles "nb_tiles" amount of tiles are placed in * the order they appear in the @ref AVStreamGroupTileGrid.offsets "offsets" * array, at the exact offset described for them. In particular, if two or more * tiles overlap, the image with higher index in the * @ref AVStreamGroupTileGrid.offsets "offsets" array takes priority. * Note that a single image may be used multiple times, i.e. multiple entries * in @ref AVStreamGroupTileGrid.offsets "offsets" may have the same value of * idx. * * The following is an example of a simple grid with 3 rows and 4 columns: * * +---+---+---+---+ * | 0 | 1 | 2 | 3 | * +---+---+---+---+ * | 4 | 5 | 6 | 7 | * +---+---+---+---+ * | 8 | 9 |10 |11 | * +---+---+---+---+ * * Assuming all tiles have a dimension of 512x512, the * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of * the first @ref AVStreamGroup.streams "stream" in the group is "0,0", the * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of * the second @ref AVStreamGroup.streams "stream" in the group is "512,0", the * @ref AVStreamGroupTileGrid.offsets "offset" of the topleft pixel of * the fifth @ref AVStreamGroup.streams "stream" in the group is "0,512", the * @ref AVStreamGroupTileGrid.offsets "offset", of the topleft pixel of * the sixth @ref AVStreamGroup.streams "stream" in the group is "512,512", * etc. * * The following is an example of a canvas with overlaping tiles: * * +-----------+ * | %%%%% | * |***%%3%%@@@| * |**0%%%%%2@@| * |***##1@@@@@| * | ##### | * +-----------+ * * Assuming a canvas with size 1024x1024 and all tiles with a dimension of * 512x512, a possible @ref AVStreamGroupTileGrid.offsets "offset" for the * topleft pixel of the first @ref AVStreamGroup.streams "stream" in the group * would be 0x256, the @ref AVStreamGroupTileGrid.offsets "offset" for the * topleft pixel of the second @ref AVStreamGroup.streams "stream" in the group * would be 256x512, the @ref AVStreamGroupTileGrid.offsets "offset" for the * topleft pixel of the third @ref AVStreamGroup.streams "stream" in the group * would be 512x256, and the @ref AVStreamGroupTileGrid.offsets "offset" for * the topleft pixel of the fourth @ref AVStreamGroup.streams "stream" in the * group would be 256x0. * * sizeof(AVStreamGroupTileGrid) is not a part of the ABI and may only be * allocated by avformat_stream_group_create(). */ AVStreamGroupTileGrid; enum AVStreamGroupParamsType { … }; struct AVIAMFAudioElement; struct AVIAMFMixPresentation; AVStreamGroup; struct AVCodecParserContext *av_stream_get_parser(const AVStream *s); // Chromium: We use the internal field first_dts vvv int64_t av_stream_get_first_dts(const AVStream *st); // Chromium: We use the internal field first_dts ^^^ #define AV_PROGRAM_RUNNING … /** * New fields can be added to the end with minor version bumps. * Removal, reordering and changes to existing fields require a major * version bump. * sizeof(AVProgram) must not be used outside libav*. */ AVProgram; #define AVFMTCTX_NOHEADER … #define AVFMTCTX_UNSEEKABLE … AVChapter; /** * Callback used by devices to communicate with application. */ av_format_control_message; AVOpenCallback; /** * The duration of a video can be estimated through various ways, and this enum can be used * to know how the duration was estimated. */ enum AVDurationEstimationMethod { … }; /** * Format I/O context. * New fields can be added to the end with minor version bumps. * Removal, reordering and changes to existing fields require a major * version bump. * sizeof(AVFormatContext) must not be used outside libav*, use * avformat_alloc_context() to create an AVFormatContext. * * Fields can be accessed through AVOptions (av_opt*), * the name string used matches the associated command line parameter name and * can be found in libavformat/options_table.h. * The AVOption/command line parameter names differ in some cases from the C * structure field names for historic reasons or brevity. */ AVFormatContext; /** * This function will cause global side data to be injected in the next packet * of each stream as well as after any subsequent seek. * * @note global side data is always available in every AVStream's * @ref AVCodecParameters.coded_side_data "codecpar side data" array, and * in a @ref AVCodecContext.coded_side_data "decoder's side data" array if * initialized with said stream's codecpar. * @see av_packet_side_data_get() */ void av_format_inject_global_side_data(AVFormatContext *s); #if FF_API_GET_DUR_ESTIMATE_METHOD /** * Returns the method used to set ctx->duration. * * @return AVFMT_DURATION_FROM_PTS, AVFMT_DURATION_FROM_STREAM, or AVFMT_DURATION_FROM_BITRATE. * @deprecated duration_estimation_method is public and can be read directly. */ attribute_deprecated enum AVDurationEstimationMethod av_fmt_ctx_get_duration_estimation_method(const AVFormatContext* ctx); #endif /** * @defgroup lavf_core Core functions * @ingroup libavf * * Functions for querying libavformat capabilities, allocating core structures, * etc. * @{ */ /** * Return the LIBAVFORMAT_VERSION_INT constant. */ unsigned avformat_version(void); /** * Return the libavformat build-time configuration. */ const char *avformat_configuration(void); /** * Return the libavformat license. */ const char *avformat_license(void); /** * Do global initialization of network libraries. This is optional, * and not recommended anymore. * * This functions only exists to work around thread-safety issues * with older GnuTLS or OpenSSL libraries. If libavformat is linked * to newer versions of those libraries, or if you do not use them, * calling this function is unnecessary. Otherwise, you need to call * this function before any other threads using them are started. * * This function will be deprecated once support for older GnuTLS and * OpenSSL libraries is removed, and this function has no purpose * anymore. */ int avformat_network_init(void); /** * Undo the initialization done by avformat_network_init. Call it only * once for each time you called avformat_network_init. */ int avformat_network_deinit(void); /** * Iterate over all registered muxers. * * @param opaque a pointer where libavformat will store the iteration state. Must * point to NULL to start the iteration. * * @return the next registered muxer or NULL when the iteration is * finished */ const AVOutputFormat *av_muxer_iterate(void **opaque); /** * Iterate over all registered demuxers. * * @param opaque a pointer where libavformat will store the iteration state. * Must point to NULL to start the iteration. * * @return the next registered demuxer or NULL when the iteration is * finished */ const AVInputFormat *av_demuxer_iterate(void **opaque); /** * Allocate an AVFormatContext. * avformat_free_context() can be used to free the context and everything * allocated by the framework within it. */ AVFormatContext *avformat_alloc_context(void); /** * Free an AVFormatContext and all its streams. * @param s context to free */ void avformat_free_context(AVFormatContext *s); /** * Get the AVClass for AVFormatContext. It can be used in combination with * AV_OPT_SEARCH_FAKE_OBJ for examining options. * * @see av_opt_find(). */ const AVClass *avformat_get_class(void); /** * Get the AVClass for AVStream. It can be used in combination with * AV_OPT_SEARCH_FAKE_OBJ for examining options. * * @see av_opt_find(). */ const AVClass *av_stream_get_class(void); /** * Get the AVClass for AVStreamGroup. It can be used in combination with * AV_OPT_SEARCH_FAKE_OBJ for examining options. * * @see av_opt_find(). */ const AVClass *av_stream_group_get_class(void); /** * @return a string identifying the stream group type, or NULL if unknown */ const char *avformat_stream_group_name(enum AVStreamGroupParamsType type); /** * Add a new empty stream group to a media file. * * When demuxing, it may be called by the demuxer in read_header(). If the * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also * be called in read_packet(). * * When muxing, may be called by the user before avformat_write_header(). * * User is required to call avformat_free_context() to clean up the allocation * by avformat_stream_group_create(). * * New streams can be added to the group with avformat_stream_group_add_stream(). * * @param s media file handle * * @return newly created group or NULL on error. * @see avformat_new_stream, avformat_stream_group_add_stream. */ AVStreamGroup *avformat_stream_group_create(AVFormatContext *s, enum AVStreamGroupParamsType type, AVDictionary **options); /** * Add a new stream to a media file. * * When demuxing, it is called by the demuxer in read_header(). If the * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also * be called in read_packet(). * * When muxing, should be called by the user before avformat_write_header(). * * User is required to call avformat_free_context() to clean up the allocation * by avformat_new_stream(). * * @param s media file handle * @param c unused, does nothing * * @return newly created stream or NULL on error. */ AVStream *avformat_new_stream(AVFormatContext *s, const struct AVCodec *c); /** * Add an already allocated stream to a stream group. * * When demuxing, it may be called by the demuxer in read_header(). If the * flag AVFMTCTX_NOHEADER is set in s.ctx_flags, then it may also * be called in read_packet(). * * When muxing, may be called by the user before avformat_write_header() after * having allocated a new group with avformat_stream_group_create() and stream with * avformat_new_stream(). * * User is required to call avformat_free_context() to clean up the allocation * by avformat_stream_group_add_stream(). * * @param stg stream group belonging to a media file. * @param st stream in the media file to add to the group. * * @retval 0 success * @retval AVERROR(EEXIST) the stream was already in the group * @retval "another negative error code" legitimate errors * * @see avformat_new_stream, avformat_stream_group_create. */ int avformat_stream_group_add_stream(AVStreamGroup *stg, AVStream *st); #if FF_API_AVSTREAM_SIDE_DATA /** * Wrap an existing array as stream side data. * * @param st stream * @param type side information type * @param data the side data array. It must be allocated with the av_malloc() * family of functions. The ownership of the data is transferred to * st. * @param size side information size * * @return zero on success, a negative AVERROR code on failure. On failure, * the stream is unchanged and the data remains owned by the caller. * @deprecated use av_packet_side_data_add() with the stream's * @ref AVCodecParameters.coded_side_data "codecpar side data" */ attribute_deprecated int av_stream_add_side_data(AVStream *st, enum AVPacketSideDataType type, uint8_t *data, size_t size); /** * Allocate new information from stream. * * @param stream stream * @param type desired side information type * @param size side information size * * @return pointer to fresh allocated data or NULL otherwise * @deprecated use av_packet_side_data_new() with the stream's * @ref AVCodecParameters.coded_side_data "codecpar side data" */ attribute_deprecated uint8_t *av_stream_new_side_data(AVStream *stream, enum AVPacketSideDataType type, size_t size); /** * Get side information from stream. * * @param stream stream * @param type desired side information type * @param size If supplied, *size will be set to the size of the side data * or to zero if the desired side data is not present. * * @return pointer to data if present or NULL otherwise * @deprecated use av_packet_side_data_get() with the stream's * @ref AVCodecParameters.coded_side_data "codecpar side data" */ attribute_deprecated uint8_t *av_stream_get_side_data(const AVStream *stream, enum AVPacketSideDataType type, size_t *size); #endif AVProgram *av_new_program(AVFormatContext *s, int id); /** * @} */ /** * Allocate an AVFormatContext for an output format. * avformat_free_context() can be used to free the context and * everything allocated by the framework within it. * * @param ctx pointee is set to the created format context, * or to NULL in case of failure * @param oformat format to use for allocating the context, if NULL * format_name and filename are used instead * @param format_name the name of output format to use for allocating the * context, if NULL filename is used instead * @param filename the name of the filename to use for allocating the * context, may be NULL * * @return >= 0 in case of success, a negative AVERROR code in case of * failure */ int avformat_alloc_output_context2(AVFormatContext **ctx, const AVOutputFormat *oformat, const char *format_name, const char *filename); /** * @addtogroup lavf_decoding * @{ */ /** * Find AVInputFormat based on the short name of the input format. */ const AVInputFormat *av_find_input_format(const char *short_name); /** * Guess the file format. * * @param pd data to be probed * @param is_opened Whether the file is already opened; determines whether * demuxers with or without AVFMT_NOFILE are probed. */ const AVInputFormat *av_probe_input_format(const AVProbeData *pd, int is_opened); /** * Guess the file format. * * @param pd data to be probed * @param is_opened Whether the file is already opened; determines whether * demuxers with or without AVFMT_NOFILE are probed. * @param score_max A probe score larger that this is required to accept a * detection, the variable is set to the actual detection * score afterwards. * If the score is <= AVPROBE_SCORE_MAX / 4 it is recommended * to retry with a larger probe buffer. */ const AVInputFormat *av_probe_input_format2(const AVProbeData *pd, int is_opened, int *score_max); /** * Guess the file format. * * @param is_opened Whether the file is already opened; determines whether * demuxers with or without AVFMT_NOFILE are probed. * @param score_ret The score of the best detection. */ const AVInputFormat *av_probe_input_format3(const AVProbeData *pd, int is_opened, int *score_ret); /** * Probe a bytestream to determine the input format. Each time a probe returns * with a score that is too low, the probe buffer size is increased and another * attempt is made. When the maximum probe size is reached, the input format * with the highest score is returned. * * @param pb the bytestream to probe * @param fmt the input format is put here * @param url the url of the stream * @param logctx the log context * @param offset the offset within the bytestream to probe from * @param max_probe_size the maximum probe buffer size (zero for default) * * @return the score in case of success, a negative value corresponding to an * the maximal score is AVPROBE_SCORE_MAX * AVERROR code otherwise */ int av_probe_input_buffer2(AVIOContext *pb, const AVInputFormat **fmt, const char *url, void *logctx, unsigned int offset, unsigned int max_probe_size); /** * Like av_probe_input_buffer2() but returns 0 on success */ int av_probe_input_buffer(AVIOContext *pb, const AVInputFormat **fmt, const char *url, void *logctx, unsigned int offset, unsigned int max_probe_size); /** * Open an input stream and read the header. The codecs are not opened. * The stream must be closed with avformat_close_input(). * * @param ps Pointer to user-supplied AVFormatContext (allocated by * avformat_alloc_context). May be a pointer to NULL, in * which case an AVFormatContext is allocated by this * function and written into ps. * Note that a user-supplied AVFormatContext will be freed * on failure. * @param url URL of the stream to open. * @param fmt If non-NULL, this parameter forces a specific input format. * Otherwise the format is autodetected. * @param options A dictionary filled with AVFormatContext and demuxer-private * options. * On return this parameter will be destroyed and replaced with * a dict containing options that were not found. May be NULL. * * @return 0 on success, a negative AVERROR on failure. * * @note If you want to use custom IO, preallocate the format context and set its pb field. */ int avformat_open_input(AVFormatContext **ps, const char *url, const AVInputFormat *fmt, AVDictionary **options); /** * Read packets of a media file to get stream information. This * is useful for file formats with no headers such as MPEG. This * function also computes the real framerate in case of MPEG-2 repeat * frame mode. * The logical file position is not changed by this function; * examined packets may be buffered for later processing. * * @param ic media file handle * @param options If non-NULL, an ic.nb_streams long array of pointers to * dictionaries, where i-th member contains options for * codec corresponding to i-th stream. * On return each dictionary will be filled with options that were not found. * @return >=0 if OK, AVERROR_xxx on error * * @note this function isn't guaranteed to open all the codecs, so * options being non-empty at return is a perfectly normal behavior. * * @todo Let the user decide somehow what information is needed so that * we do not waste time getting stuff the user does not need. */ int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options); /** * Find the programs which belong to a given stream. * * @param ic media file handle * @param last the last found program, the search will start after this * program, or from the beginning if it is NULL * @param s stream index * * @return the next program which belongs to s, NULL if no program is found or * the last program is not among the programs of ic. */ AVProgram *av_find_program_from_stream(AVFormatContext *ic, AVProgram *last, int s); void av_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx); /** * Find the "best" stream in the file. * The best stream is determined according to various heuristics as the most * likely to be what the user expects. * If the decoder parameter is non-NULL, av_find_best_stream will find the * default decoder for the stream's codec; streams for which no decoder can * be found are ignored. * * @param ic media file handle * @param type stream type: video, audio, subtitles, etc. * @param wanted_stream_nb user-requested stream number, * or -1 for automatic selection * @param related_stream try to find a stream related (eg. in the same * program) to this one, or -1 if none * @param decoder_ret if non-NULL, returns the decoder for the * selected stream * @param flags flags; none are currently defined * * @return the non-negative stream number in case of success, * AVERROR_STREAM_NOT_FOUND if no stream with the requested type * could be found, * AVERROR_DECODER_NOT_FOUND if streams were found but no decoder * * @note If av_find_best_stream returns successfully and decoder_ret is not * NULL, then *decoder_ret is guaranteed to be set to a valid AVCodec. */ int av_find_best_stream(AVFormatContext *ic, enum AVMediaType type, int wanted_stream_nb, int related_stream, const struct AVCodec **decoder_ret, int flags); /** * Return the next frame of a stream. * This function returns what is stored in the file, and does not validate * that what is there are valid frames for the decoder. It will split what is * stored in the file into frames and return one for each call. It will not * omit invalid data between valid frames so as to give the decoder the maximum * information possible for decoding. * * On success, the returned packet is reference-counted (pkt->buf is set) and * valid indefinitely. The packet must be freed with av_packet_unref() when * it is no longer needed. For video, the packet contains exactly one frame. * For audio, it contains an integer number of frames if each frame has * a known fixed size (e.g. PCM or ADPCM data). If the audio frames have * a variable size (e.g. MPEG audio), then it contains one frame. * * pkt->pts, pkt->dts and pkt->duration are always set to correct * values in AVStream.time_base units (and guessed if the format cannot * provide them). pkt->pts can be AV_NOPTS_VALUE if the video format * has B-frames, so it is better to rely on pkt->dts if you do not * decompress the payload. * * @return 0 if OK, < 0 on error or end of file. On error, pkt will be blank * (as if it came from av_packet_alloc()). * * @note pkt will be initialized, so it may be uninitialized, but it must not * contain data that needs to be freed. */ int av_read_frame(AVFormatContext *s, AVPacket *pkt); /** * Seek to the keyframe at timestamp. * 'timestamp' in 'stream_index'. * * @param s media file handle * @param stream_index If stream_index is (-1), a default stream is selected, * and timestamp is automatically converted from * AV_TIME_BASE units to the stream specific time_base. * @param timestamp Timestamp in AVStream.time_base units or, if no stream * is specified, in AV_TIME_BASE units. * @param flags flags which select direction and seeking mode * * @return >= 0 on success */ int av_seek_frame(AVFormatContext *s, int stream_index, int64_t timestamp, int flags); /** * Seek to timestamp ts. * Seeking will be done so that the point from which all active streams * can be presented successfully will be closest to ts and within min/max_ts. * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL. * * If flags contain AVSEEK_FLAG_BYTE, then all timestamps are in bytes and * are the file position (this may not be supported by all demuxers). * If flags contain AVSEEK_FLAG_FRAME, then all timestamps are in frames * in the stream with stream_index (this may not be supported by all demuxers). * Otherwise all timestamps are in units of the stream selected by stream_index * or if stream_index is -1, in AV_TIME_BASE units. * If flags contain AVSEEK_FLAG_ANY, then non-keyframes are treated as * keyframes (this may not be supported by all demuxers). * If flags contain AVSEEK_FLAG_BACKWARD, it is ignored. * * @param s media file handle * @param stream_index index of the stream which is used as time base reference * @param min_ts smallest acceptable timestamp * @param ts target timestamp * @param max_ts largest acceptable timestamp * @param flags flags * @return >=0 on success, error code otherwise * * @note This is part of the new seek API which is still under construction. */ int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags); /** * Discard all internally buffered data. This can be useful when dealing with * discontinuities in the byte stream. Generally works only with formats that * can resync. This includes headerless formats like MPEG-TS/TS but should also * work with NUT, Ogg and in a limited way AVI for example. * * The set of streams, the detected duration, stream parameters and codecs do * not change when calling this function. If you want a complete reset, it's * better to open a new AVFormatContext. * * This does not flush the AVIOContext (s->pb). If necessary, call * avio_flush(s->pb) before calling this function. * * @param s media file handle * @return >=0 on success, error code otherwise */ int avformat_flush(AVFormatContext *s); /** * Start playing a network-based stream (e.g. RTSP stream) at the * current position. */ int av_read_play(AVFormatContext *s); /** * Pause a network-based stream (e.g. RTSP stream). * * Use av_read_play() to resume it. */ int av_read_pause(AVFormatContext *s); /** * Close an opened input AVFormatContext. Free it and all its contents * and set *s to NULL. */ void avformat_close_input(AVFormatContext **s); /** * @} */ #define AVSEEK_FLAG_BACKWARD … #define AVSEEK_FLAG_BYTE … #define AVSEEK_FLAG_ANY … #define AVSEEK_FLAG_FRAME … /** * @addtogroup lavf_encoding * @{ */ #define AVSTREAM_INIT_IN_WRITE_HEADER … #define AVSTREAM_INIT_IN_INIT_OUTPUT … /** * Allocate the stream private data and write the stream header to * an output media file. * * @param s Media file handle, must be allocated with * avformat_alloc_context(). * Its \ref AVFormatContext.oformat "oformat" field must be set * to the desired output format; * Its \ref AVFormatContext.pb "pb" field must be set to an * already opened ::AVIOContext. * @param options An ::AVDictionary filled with AVFormatContext and * muxer-private options. * On return this parameter will be destroyed and replaced with * a dict containing options that were not found. May be NULL. * * @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec had not already been * fully initialized in avformat_init_output(). * @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec had already been fully * initialized in avformat_init_output(). * @retval AVERROR A negative AVERROR on failure. * * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_init_output. */ av_warn_unused_result int avformat_write_header(AVFormatContext *s, AVDictionary **options); /** * Allocate the stream private data and initialize the codec, but do not write the header. * May optionally be used before avformat_write_header() to initialize stream parameters * before actually writing the header. * If using this function, do not pass the same options to avformat_write_header(). * * @param s Media file handle, must be allocated with * avformat_alloc_context(). * Its \ref AVFormatContext.oformat "oformat" field must be set * to the desired output format; * Its \ref AVFormatContext.pb "pb" field must be set to an * already opened ::AVIOContext. * @param options An ::AVDictionary filled with AVFormatContext and * muxer-private options. * On return this parameter will be destroyed and replaced with * a dict containing options that were not found. May be NULL. * * @retval AVSTREAM_INIT_IN_WRITE_HEADER On success, if the codec requires * avformat_write_header to fully initialize. * @retval AVSTREAM_INIT_IN_INIT_OUTPUT On success, if the codec has been fully * initialized. * @retval AVERROR Anegative AVERROR on failure. * * @see av_opt_find, av_dict_set, avio_open, av_oformat_next, avformat_write_header. */ av_warn_unused_result int avformat_init_output(AVFormatContext *s, AVDictionary **options); /** * Write a packet to an output media file. * * This function passes the packet directly to the muxer, without any buffering * or reordering. The caller is responsible for correctly interleaving the * packets if the format requires it. Callers that want libavformat to handle * the interleaving should call av_interleaved_write_frame() instead of this * function. * * @param s media file handle * @param pkt The packet containing the data to be written. Note that unlike * av_interleaved_write_frame(), this function does not take * ownership of the packet passed to it (though some muxers may make * an internal reference to the input packet). * <br> * This parameter can be NULL (at any time, not just at the end), in * order to immediately flush data buffered within the muxer, for * muxers that buffer up data internally before writing it to the * output. * <br> * Packet's @ref AVPacket.stream_index "stream_index" field must be * set to the index of the corresponding stream in @ref * AVFormatContext.streams "s->streams". * <br> * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts") * must be set to correct values in the stream's timebase (unless the * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then * they can be set to AV_NOPTS_VALUE). * The dts for subsequent packets passed to this function must be strictly * increasing when compared in their respective timebases (unless the * output format is flagged with the AVFMT_TS_NONSTRICT, then they * merely have to be nondecreasing). @ref AVPacket.duration * "duration") should also be set if known. * @return < 0 on error, = 0 if OK, 1 if flushed and there is no more data to flush * * @see av_interleaved_write_frame() */ int av_write_frame(AVFormatContext *s, AVPacket *pkt); /** * Write a packet to an output media file ensuring correct interleaving. * * This function will buffer the packets internally as needed to make sure the * packets in the output file are properly interleaved, usually ordered by * increasing dts. Callers doing their own interleaving should call * av_write_frame() instead of this function. * * Using this function instead of av_write_frame() can give muxers advance * knowledge of future packets, improving e.g. the behaviour of the mp4 * muxer for VFR content in fragmenting mode. * * @param s media file handle * @param pkt The packet containing the data to be written. * <br> * If the packet is reference-counted, this function will take * ownership of this reference and unreference it later when it sees * fit. If the packet is not reference-counted, libavformat will * make a copy. * The returned packet will be blank (as if returned from * av_packet_alloc()), even on error. * <br> * This parameter can be NULL (at any time, not just at the end), to * flush the interleaving queues. * <br> * Packet's @ref AVPacket.stream_index "stream_index" field must be * set to the index of the corresponding stream in @ref * AVFormatContext.streams "s->streams". * <br> * The timestamps (@ref AVPacket.pts "pts", @ref AVPacket.dts "dts") * must be set to correct values in the stream's timebase (unless the * output format is flagged with the AVFMT_NOTIMESTAMPS flag, then * they can be set to AV_NOPTS_VALUE). * The dts for subsequent packets in one stream must be strictly * increasing (unless the output format is flagged with the * AVFMT_TS_NONSTRICT, then they merely have to be nondecreasing). * @ref AVPacket.duration "duration" should also be set if known. * * @return 0 on success, a negative AVERROR on error. * * @see av_write_frame(), AVFormatContext.max_interleave_delta */ int av_interleaved_write_frame(AVFormatContext *s, AVPacket *pkt); /** * Write an uncoded frame to an output media file. * * The frame must be correctly interleaved according to the container * specification; if not, av_interleaved_write_uncoded_frame() must be used. * * See av_interleaved_write_uncoded_frame() for details. */ int av_write_uncoded_frame(AVFormatContext *s, int stream_index, struct AVFrame *frame); /** * Write an uncoded frame to an output media file. * * If the muxer supports it, this function makes it possible to write an AVFrame * structure directly, without encoding it into a packet. * It is mostly useful for devices and similar special muxers that use raw * video or PCM data and will not serialize it into a byte stream. * * To test whether it is possible to use it with a given muxer and stream, * use av_write_uncoded_frame_query(). * * The caller gives up ownership of the frame and must not access it * afterwards. * * @return >=0 for success, a negative code on error */ int av_interleaved_write_uncoded_frame(AVFormatContext *s, int stream_index, struct AVFrame *frame); /** * Test whether a muxer supports uncoded frame. * * @return >=0 if an uncoded frame can be written to that muxer and stream, * <0 if not */ int av_write_uncoded_frame_query(AVFormatContext *s, int stream_index); /** * Write the stream trailer to an output media file and free the * file private data. * * May only be called after a successful call to avformat_write_header. * * @param s media file handle * @return 0 if OK, AVERROR_xxx on error */ int av_write_trailer(AVFormatContext *s); /** * Return the output format in the list of registered output formats * which best matches the provided parameters, or return NULL if * there is no match. * * @param short_name if non-NULL checks if short_name matches with the * names of the registered formats * @param filename if non-NULL checks if filename terminates with the * extensions of the registered formats * @param mime_type if non-NULL checks if mime_type matches with the * MIME type of the registered formats */ const AVOutputFormat *av_guess_format(const char *short_name, const char *filename, const char *mime_type); /** * Guess the codec ID based upon muxer and filename. */ enum AVCodecID av_guess_codec(const AVOutputFormat *fmt, const char *short_name, const char *filename, const char *mime_type, enum AVMediaType type); /** * Get timing information for the data currently output. * The exact meaning of "currently output" depends on the format. * It is mostly relevant for devices that have an internal buffer and/or * work in real time. * @param s media file handle * @param stream stream in the media file * @param[out] dts DTS of the last packet output for the stream, in stream * time_base units * @param[out] wall absolute time when that packet whas output, * in microsecond * @retval 0 Success * @retval AVERROR(ENOSYS) The format does not support it * * @note Some formats or devices may not allow to measure dts and wall * atomically. */ int av_get_output_timestamp(struct AVFormatContext *s, int stream, int64_t *dts, int64_t *wall); /** * @} */ /** * @defgroup lavf_misc Utility functions * @ingroup libavf * @{ * * Miscellaneous utility functions related to both muxing and demuxing * (or neither). */ /** * Send a nice hexadecimal dump of a buffer to the specified file stream. * * @param f The file stream pointer where the dump should be sent to. * @param buf buffer * @param size buffer size * * @see av_hex_dump_log, av_pkt_dump2, av_pkt_dump_log2 */ void av_hex_dump(FILE *f, const uint8_t *buf, int size); /** * Send a nice hexadecimal dump of a buffer to the log. * * @param avcl A pointer to an arbitrary struct of which the first field is a * pointer to an AVClass struct. * @param level The importance level of the message, lower values signifying * higher importance. * @param buf buffer * @param size buffer size * * @see av_hex_dump, av_pkt_dump2, av_pkt_dump_log2 */ void av_hex_dump_log(void *avcl, int level, const uint8_t *buf, int size); /** * Send a nice dump of a packet to the specified file stream. * * @param f The file stream pointer where the dump should be sent to. * @param pkt packet to dump * @param dump_payload True if the payload must be displayed, too. * @param st AVStream that the packet belongs to */ void av_pkt_dump2(FILE *f, const AVPacket *pkt, int dump_payload, const AVStream *st); /** * Send a nice dump of a packet to the log. * * @param avcl A pointer to an arbitrary struct of which the first field is a * pointer to an AVClass struct. * @param level The importance level of the message, lower values signifying * higher importance. * @param pkt packet to dump * @param dump_payload True if the payload must be displayed, too. * @param st AVStream that the packet belongs to */ void av_pkt_dump_log2(void *avcl, int level, const AVPacket *pkt, int dump_payload, const AVStream *st); /** * Get the AVCodecID for the given codec tag tag. * If no codec id is found returns AV_CODEC_ID_NONE. * * @param tags list of supported codec_id-codec_tag pairs, as stored * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag * @param tag codec tag to match to a codec ID */ enum AVCodecID av_codec_get_id(const struct AVCodecTag * const *tags, unsigned int tag); /** * Get the codec tag for the given codec id id. * If no codec tag is found returns 0. * * @param tags list of supported codec_id-codec_tag pairs, as stored * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag * @param id codec ID to match to a codec tag */ unsigned int av_codec_get_tag(const struct AVCodecTag * const *tags, enum AVCodecID id); /** * Get the codec tag for the given codec id. * * @param tags list of supported codec_id - codec_tag pairs, as stored * in AVInputFormat.codec_tag and AVOutputFormat.codec_tag * @param id codec id that should be searched for in the list * @param tag A pointer to the found tag * @return 0 if id was not found in tags, > 0 if it was found */ int av_codec_get_tag2(const struct AVCodecTag * const *tags, enum AVCodecID id, unsigned int *tag); int av_find_default_stream_index(AVFormatContext *s); /** * Get the index for a specific timestamp. * * @param st stream that the timestamp belongs to * @param timestamp timestamp to retrieve the index for * @param flags if AVSEEK_FLAG_BACKWARD then the returned index will correspond * to the timestamp which is <= the requested one, if backward * is 0, then it will be >= * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise * @return < 0 if no such timestamp could be found */ int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags); /** * Get the index entry count for the given AVStream. * * @param st stream * @return the number of index entries in the stream */ int avformat_index_get_entries_count(const AVStream *st); /** * Get the AVIndexEntry corresponding to the given index. * * @param st Stream containing the requested AVIndexEntry. * @param idx The desired index. * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise. * * @note The pointer returned by this function is only guaranteed to be valid * until any function that takes the stream or the parent AVFormatContext * as input argument is called. */ const AVIndexEntry *avformat_index_get_entry(AVStream *st, int idx); /** * Get the AVIndexEntry corresponding to the given timestamp. * * @param st Stream containing the requested AVIndexEntry. * @param wanted_timestamp Timestamp to retrieve the index entry for. * @param flags If AVSEEK_FLAG_BACKWARD then the returned entry will correspond * to the timestamp which is <= the requested one, if backward * is 0, then it will be >= * if AVSEEK_FLAG_ANY seek to any frame, only keyframes otherwise. * @return A pointer to the requested AVIndexEntry if it exists, NULL otherwise. * * @note The pointer returned by this function is only guaranteed to be valid * until any function that takes the stream or the parent AVFormatContext * as input argument is called. */ const AVIndexEntry *avformat_index_get_entry_from_timestamp(AVStream *st, int64_t wanted_timestamp, int flags); /** * Add an index entry into a sorted list. Update the entry if the list * already contains it. * * @param timestamp timestamp in the time base of the given stream */ int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags); /** * Split a URL string into components. * * The pointers to buffers for storing individual components may be null, * in order to ignore that component. Buffers for components not found are * set to empty strings. If the port is not found, it is set to a negative * value. * * @param proto the buffer for the protocol * @param proto_size the size of the proto buffer * @param authorization the buffer for the authorization * @param authorization_size the size of the authorization buffer * @param hostname the buffer for the host name * @param hostname_size the size of the hostname buffer * @param port_ptr a pointer to store the port number in * @param path the buffer for the path * @param path_size the size of the path buffer * @param url the URL to split */ void av_url_split(char *proto, int proto_size, char *authorization, int authorization_size, char *hostname, int hostname_size, int *port_ptr, char *path, int path_size, const char *url); /** * Print detailed information about the input or output format, such as * duration, bitrate, streams, container, programs, metadata, side data, * codec and time base. * * @param ic the context to analyze * @param index index of the stream to dump information about * @param url the URL to print, such as source or destination file * @param is_output Select whether the specified context is an input(0) or output(1) */ void av_dump_format(AVFormatContext *ic, int index, const char *url, int is_output); #define AV_FRAME_FILENAME_FLAGS_MULTIPLE … /** * Return in 'buf' the path with '%d' replaced by a number. * * Also handles the '%0nd' format where 'n' is the total number * of digits and '%%'. * * @param buf destination buffer * @param buf_size destination buffer size * @param path numbered sequence string * @param number frame number * @param flags AV_FRAME_FILENAME_FLAGS_* * @return 0 if OK, -1 on format error */ int av_get_frame_filename2(char *buf, int buf_size, const char *path, int number, int flags); int av_get_frame_filename(char *buf, int buf_size, const char *path, int number); /** * Check whether filename actually is a numbered sequence generator. * * @param filename possible numbered sequence string * @return 1 if a valid numbered sequence string, 0 otherwise */ int av_filename_number_test(const char *filename); /** * Generate an SDP for an RTP session. * * Note, this overwrites the id values of AVStreams in the muxer contexts * for getting unique dynamic payload types. * * @param ac array of AVFormatContexts describing the RTP streams. If the * array is composed by only one context, such context can contain * multiple AVStreams (one AVStream per RTP stream). Otherwise, * all the contexts in the array (an AVCodecContext per RTP stream) * must contain only one AVStream. * @param n_files number of AVCodecContexts contained in ac * @param buf buffer where the SDP will be stored (must be allocated by * the caller) * @param size the size of the buffer * @return 0 if OK, AVERROR_xxx on error */ int av_sdp_create(AVFormatContext *ac[], int n_files, char *buf, int size); /** * Return a positive value if the given filename has one of the given * extensions, 0 otherwise. * * @param filename file name to check against the given extensions * @param extensions a comma-separated list of filename extensions */ int av_match_ext(const char *filename, const char *extensions); /** * Test if the given container can store a codec. * * @param ofmt container to check for compatibility * @param codec_id codec to potentially store in container * @param std_compliance standards compliance level, one of FF_COMPLIANCE_* * * @return 1 if codec with ID codec_id can be stored in ofmt, 0 if it cannot. * A negative number if this information is not available. */ int avformat_query_codec(const AVOutputFormat *ofmt, enum AVCodecID codec_id, int std_compliance); /** * @defgroup riff_fourcc RIFF FourCCs * @{ * Get the tables mapping RIFF FourCCs to libavcodec AVCodecIDs. The tables are * meant to be passed to av_codec_get_id()/av_codec_get_tag() as in the * following code: * @code * uint32_t tag = MKTAG('H', '2', '6', '4'); * const struct AVCodecTag *table[] = { avformat_get_riff_video_tags(), 0 }; * enum AVCodecID id = av_codec_get_id(table, tag); * @endcode */ /** * @return the table mapping RIFF FourCCs for video to libavcodec AVCodecID. */ const struct AVCodecTag *avformat_get_riff_video_tags(void); /** * @return the table mapping RIFF FourCCs for audio to AVCodecID. */ const struct AVCodecTag *avformat_get_riff_audio_tags(void); /** * @return the table mapping MOV FourCCs for video to libavcodec AVCodecID. */ const struct AVCodecTag *avformat_get_mov_video_tags(void); /** * @return the table mapping MOV FourCCs for audio to AVCodecID. */ const struct AVCodecTag *avformat_get_mov_audio_tags(void); /** * @} */ /** * Guess the sample aspect ratio of a frame, based on both the stream and the * frame aspect ratio. * * Since the frame aspect ratio is set by the codec but the stream aspect ratio * is set by the demuxer, these two may not be equal. This function tries to * return the value that you should use if you would like to display the frame. * * Basic logic is to use the stream aspect ratio if it is set to something sane * otherwise use the frame aspect ratio. This way a container setting, which is * usually easy to modify can override the coded value in the frames. * * @param format the format context which the stream is part of * @param stream the stream which the frame is part of * @param frame the frame with the aspect ratio to be determined * @return the guessed (valid) sample_aspect_ratio, 0/1 if no idea */ AVRational av_guess_sample_aspect_ratio(AVFormatContext *format, AVStream *stream, struct AVFrame *frame); /** * Guess the frame rate, based on both the container and codec information. * * @param ctx the format context which the stream is part of * @param stream the stream which the frame is part of * @param frame the frame for which the frame rate should be determined, may be NULL * @return the guessed (valid) frame rate, 0/1 if no idea */ AVRational av_guess_frame_rate(AVFormatContext *ctx, AVStream *stream, struct AVFrame *frame); /** * Check if the stream st contained in s is matched by the stream specifier * spec. * * See the "stream specifiers" chapter in the documentation for the syntax * of spec. * * @return >0 if st is matched by spec; * 0 if st is not matched by spec; * AVERROR code if spec is invalid * * @note A stream specifier can match several streams in the format. */ int avformat_match_stream_specifier(AVFormatContext *s, AVStream *st, const char *spec); int avformat_queue_attached_pictures(AVFormatContext *s); enum AVTimebaseSource { … }; /** * Transfer internal timing information from one stream to another. * * This function is useful when doing stream copy. * * @param ofmt target output format for ost * @param ost output stream which needs timings copy and adjustments * @param ist reference input stream to copy timings from * @param copy_tb define from where the stream codec timebase needs to be imported */ int avformat_transfer_internal_stream_timing_info(const AVOutputFormat *ofmt, AVStream *ost, const AVStream *ist, enum AVTimebaseSource copy_tb); /** * Get the internal codec timebase from a stream. * * @param st input stream to extract the timebase from */ AVRational av_stream_get_codec_timebase(const AVStream *st); /** * @} */ #endif /* AVFORMAT_AVFORMAT_H */
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